作者：Pascal Luban

今天我将阐述游戏开发过程中另外一个重要方面，即有游戏平衡性问题。（请点击此处阅读本系列第1、第2篇）

协调性

平衡性是指任何玩家或者群组都不能始终保持游戏中的优势，不论是利用游戏参数（例如武器的能量等）还是寻找地图上的漏洞。这一问题在多人游戏中特别明显，因为玩家会花大把的时间于游戏中并因此能够找到这些漏洞，而让自己获得竞争优势。因为玩家已无数次玩遍地图，他们很容易从发现任何缺陷。

地图漏洞可能会因此抹杀了整体地图的作用，而让玩家或群组够获得暂时的竞争优势。《细胞分裂2：明日潘朵拉》游戏中的仓库地图就出现了这种问题。这一地图中供划分了3块领域，而第一游戏区旁边的小房间里是专门用于制造更多防御者。显然这个房间是专门留给防御者，所以攻击者不能够轻易靠近。

但是在玩了几周的游戏后，我们发现攻击玩家找到了一个进入这个房间的技巧，即利用防御者走出房间的那个时刻。只要玩家能够进入房间，他们便能在防御者诞生时刻轻松地杀掉他们。而这种漏洞会让游戏失去可玩性。幸运的是，很少玩家会这么做，因为地图上划分了不同区域，所以只要玩家完成了第一个区域的任务，他们便会自然地移动到下一个区域。

糟糕的游戏平衡性会让玩家对此失去兴趣，因为没有人会愿意与那些拥有倾斜优势的游戏角色抗争。但是我们还应该注意，平衡性并不是关卡设计中唯一需要重视的内容，游戏系统和游戏设计也很重要。创造出一款平衡的多人游戏需综合考虑三大元素：关卡设计、游戏设计和游戏测试。

关卡设计

能够影响游戏平衡性的首个关卡设计方案是关于地图的尺寸以及它可容纳的玩家数量。小地图更难维持游戏的平衡，因为地图中任何微小的细节都会因玩家活动的密度和速度而加倍放大。相反地，如果地图尺寸过大，玩家也会很容易感到厌烦，因为他们能够遇到的目标实在太少了。所以玩家的数量以及地图的尺寸之间的比例非常重要。大部分情况下，我们总是会选择较大的地图。因为它们能够提供更多战术机遇，并且让玩家难以从地图漏洞中占到便宜。

地图布局本身也能够维持游戏平衡性。开放性地图（如户外场景）以及三维空间的使用更是让玩家难以从中找到漏洞。比起“单调的”室内地图，这种地图能够提供更多策略性的机遇。

最后，地图同样也应该提供给玩家各种机遇以更好地使用游戏设计功能：武器，装备，移动等。《细胞分裂2：明日潘朵拉》以及《混沌理论》的多人游戏版本的地图中都设置了许多场所，让攻击者可以更好地

躲藏起来而伏击防御者；他们还可以在较高的人行桥上监视更广泛的区域并准确地向目标投射手榴弹；并且沿着管道爬上防御者藏身的房间天花板，从上跳跃进行攻击。

游戏系统，平衡对立力量

这个观点是指提供给玩家足够的“道具”，帮他们找到解决不平衡性的对策。致力于《细胞分裂2：明日潘朵拉》以及《混沌理论》的多人游戏版本的游戏设计师很好地控制着这种游戏系统。即游戏既提供给玩家角色一些具有巨大潜能的装备，同时也提供给其对手一定的机遇。以下是一些例子：防御者所拥有的激光能够帮助他通过扫射周边区域而迅速找到攻击者的藏身处；但同时攻击者也能够从远处明显地看到这个激光

而发现防御者的地理位置，并观察他在寻找什么。攻击者通过隐形服掩饰能够减少暴露身份的风险，但是这么做同时也会限制他的行动速度。防御者在分布激光矿井时非常谨慎，但是攻击者却可以通过激活电子视觉轻松地找到到它的射线。这种方法能够进一步约束任何拥有超强能量的特定装备。

游戏测试，游戏QA

即使你投入再多的时间去“规划”游戏或关卡设计以避免潜在的游戏漏洞，也比不上让资深玩家帮你测试游戏，并且在游戏中寻找各种漏洞来得有效。

一般来说，在游戏开发阶段进行游戏测试非常重要。特别是对于多人游戏来说。玩家，通常来说是指硬核游戏玩家，总是愿意花费许多时间去探索地图上的每一个细节内容，并利用这种类型游戏中的各种策略：测试所有武器和装备，寻找关卡设计中的任何漏洞，并因此而获得竞争优势。如此，游戏或关卡设计的缺点便会够迅速暴露出来，而让游戏变得越来越无趣。所以，适当的游戏测试能够帮助设计师更好地找到关卡设计中的缺陷，或者游戏参数中的糟糕设置，如武器的能量，生命级别等。

除了作为《细胞分裂2：明日潘朵拉》和《混沌理论》的首席关卡设计师，我同时也参与了游戏测试的执行和监管工作。育碧D’Annecy工作室的主管了解游戏测试的重要性，同时他们也希望测试团队能够位于同一栋办公楼，以便开发团队和测试团队能够保持直接联系。

我们是如何利用游戏测试？

（在《细胞分裂2：明日潘朵拉》中，烟雾弹的设置便经过了多次的游戏测试。）

我们对成功策略（游戏邦注：让玩家能够系统性获取胜利，并因此让他们对游戏或地图保持长久兴趣的策略）展开系统性研究。玩家在游戏中最频繁遇到的便是“营地”点，这让他们能够以最低的曝光度发现1个或多个任务目标。

我们在游戏设置上下足了功夫。根据经验，我知道游戏特定功能（武器，装备以及行动等）的广泛使用也会根据玩家状态，玩家用于熟悉游戏的时间以及游戏设置发生巨大变化。只有由经过挑选的玩家所进行的长期游戏测试，方能确保游戏设置在经过几个小时的游戏后还能保持准确性。《细胞分裂2：明日潘朵拉》中的烟雾弹设置便经过了多次的游戏测试。事实上，这些烟不仅会模糊玩家的视野，如果停留时间过长，也会让防御者感到窒息。烟雾的影响范围以及持续时间便是游戏中的一些参数，而如果设置不合理的话，便会带来很多负面影响。如果手榴弹的威力过大，它便会成为游戏中一种力量失衡的武器，即攻击者只要投射出一个手榴弹就有可能完全至防御者于死地。相反地，如果手榴弹的效率过低，这种战术也会变得不再有趣，且玩家也不会选择使用它了。我曾经提到过，玩家总是会不惜任何代价去获取胜利。所以为了胜利，他们会快速放弃那些没有用的装备，而这时候我们投入开发这些装备的资源以及特效储存空间也就白白浪费了。

最后，我们将测试地图以及游戏控制方式的易用性。

对于开发团队来说，执行游戏测试活动是一次特别有帮助的经验。观察玩家是如何选择使用游戏道具以及如何改变道具的最初功能，以此了解他们为何不选择开发者在设计讨论会中所认可的特定装备。游戏测试是一种工具，可以用来区分我们在设计会议上所规划的优秀内容以及那些玩家真正使用的内容。

关于技术限制因素的解决方案

在这个系列文章的第一部分中，我们处理了多人游戏关卡设计中的相关问题，我提到了3个影响设计的技术限制因素：

带宽瓶颈

事件同步需求

失去对玩家行动的控制

让我们着眼于一些能够解决这些限制因素的方法：

带宽瓶颈

我们发现以前的开发者总是会维持玩家数量与行动（动画，地图事件，特效等）复杂性的平衡。而今天的开发者比起地图上的行动，反而更加关注玩家的数量。我相信这种选择将会发生变化，因为玩家也希望在多人游戏模式中体验到单人游戏中的体验，如地图动画，可破坏的背景以及物理管理等。所以，以下是一些解决带宽问题的方法。

我们可以通过一道光或者一团烟掩蔽一个复杂的动画，而避免带宽出现超负荷的情况。我们可以在《细胞分裂2：明日潘朵拉》的工厂地图上最大限度地使用这种技巧，而工厂会因为其中一名防御者引起的爆炸遭到破坏。整个房间里都是爆炸滚桶，如果一名防御者用子弹打击它们或者朝着它们发射手榴弹，这些滚桶便会爆炸。但是显然玩家对此并不感兴趣，因为房间的布局将会发生改变，而防御者的移动也会受到最大限度的约束。而如果不消耗带宽，便不能执行这些地图事件。负责地图设计的关卡设计师将能够成功处理这个事件，即设置让房屋被炸毁时，屋内的所有东西都会消失殆尽。因此，玩家不能够看到爆炸过程，而且如果玩家选择从房间外部发射弹药，烟雾也会阻挡他的视线而让他难以看到自己行动的结果（如下图所示）。

（在工厂地图的房间里，防御者可以轻松地移动：那里只有少数的地面障碍，人行桥环绕于整个房间的高处。但是如果其中一个防御者选择引爆爆炸滚桶，房间便会发生彻底的改变）

（因为受到各种倒塌下来的墙壁碎片以及被炸裂成一块块废金属的人行桥的阻挡，他们在地面上的移动速度将会放缓，并因此使得他们防御房间的任务变得更加困难。）

第二个解决方法是在地图周围分散消耗带宽的元素。用这种方法便不会同时出现两个复杂的元素。同时还必须确保这些元素彼此之间不会产生相互影响。

另外一个办法便是尝试着隐藏特定移动物体的移动，如电梯的移动可能会被一些非透明的墙隐藏起来。最后，还应该考虑到玩家可能会在电梯准备移动时向其投射手榴弹。但是爆炸却不应该干涉这种移动。

最后一个解决方法是努力压缩那些交换于游戏设备之间的数据信息。

事件同步需求

同步问题是让许多游戏玩家感到不满的重要因素。当一名优秀的玩家将准星置于移动目标上，并扣动扳机时，他肯定希望子弹能够立刻射中自己所瞄准的目标。如果你正致力于创造一款第一人称射击游戏，那么这一问题便将成为游戏开发过程的核心问题。其中主要有2大解决方法：

创建一个多服务器架构。传统意义上讲，在多人游戏期间，其中一个游戏设备充当着服务器的角色，并同步所有因用户机器引起的交互行为。这种架构能够保证所有机器间的同步性，但是却会因此减慢数据的转移速度，因为关于用户A和B的交互信息必须先通过服务器进行传输。在多服务器架构中，每台机器同时扮演着服务器和用户的角色。按照这种方法，当玩家A与玩家B进行互动时，并且其他玩家并未参与其中，那么数据将直接在A、B玩家之间进行交换。这种方法曾经用于《Soldier of Fortune》的Xbox版本游戏中，这款游戏因为高精确度而大受第一人称射击游戏群体的赞赏。比起传统的架构，多服务器架构还有一大优点便是，不会因为服务器的连接失败而破坏整体游戏进程。在多服务器架构中，玩家可以根据自己的想法随时开始并结束任何一段游戏过程。

从技术角度来看，一个较不讲究的方法便是使用仅在有效范围内有效的武器，如猎枪，火箭发射器或者手榴弹发射器。

失去对玩家行动的控制

这种做法的目标是避免太多玩家发现自己出现于相同区域，使他们之间的互动频率受到限制。关于这个问题的解决方法也同样与游戏和关卡设计两个方面密切相关。

增加任务目标的数量，并将其分散于地图上。《细胞分裂》和《战地》等系列游戏成功落实了这两大机制。在《战地》中，当玩家选择工程师角色时他便能够接近许多次要目标，如摧毁雷达站等。另外一个能够让玩家分散开来的方法便是允许玩家使用某些武器，但是前提是他们必须与同伴保持一定的距离。《战地》同样也使用了这一机制，即让玩家驾驶飞机或者控制炮台。

我最后的建议是避免使用小规模的地图。然而，你还必须谨慎地处理地图尺寸与所维持的玩家数量之间的平衡，因为如果地图太大而玩家数量太少，那么玩家便很快会对此感到厌烦。

但是这两个“优秀的”解决方法并不能长久解决多人游戏中所存在的特定技术问题。当然还存在其它解决方法。本质上来看，我的目标是关注这些问题以便它们能够在游戏的早期开发阶段得到重视。

吸引休闲游戏玩家

我认为让多人游戏变得更易亲近才是最大的挑战。

多人游戏的本质是让各种级别的玩家能够聚集在一起相互竞争。这也是这类型游戏的乐趣所在，但是它同样也难倒了不少游戏新手。与真人进行游戏对抗真的会比较有压迫感，即使这些人都是隐藏在游戏代号背后。

而休闲游戏玩家在挑战多人游戏的结果也很明显。当他们面临一个比自己厉害许多的对手时，便会屡遭打击。因此，毫无疑问，多人游戏更适合于硬核游戏玩家。如果我们希望多人游戏能够迎合更多不同类型玩家的需求，我们就必须正视这一问题。解决方法也是关于游戏和关卡设计。

我认为关于这个问题有两个解决方法：

添加有利于新手的功能

开发一款专为休闲玩家设计的游戏，但同时也具有能够满足资深玩家的深度机制。

新手功能

让我们回顾一些曾经出现在多人游戏中致力于让游戏变得更易亲近的功能。这也是我们在创造《分裂细胞3：混沌理论》多人游戏模式中曾经尝试过的。

第一个解决方法很简单也特别有效。即在游戏中添加一些协作模式。玩家与玩家间不会进行真正的血肉之战，因为这是对待敌人（即受游戏AI控制的bots）的方式。这种解决方法让各种级别的玩家能够一起游戏，并且不会因为某些玩家更厉害而备受打击，敌人就不再像人类的对手那样危险且难以预知了。同时，资深玩家还能够将自己的经验与游戏新手进行分享。最后，这种协作游戏也能够给玩家带来一定的乐趣，因为朝着一个共同的目标相互合作是人类冒险的主要推动力。育碧加拿大工作室便创造了《分裂细胞3：混沌理论》的“合作”多人游戏模式，并取得了巨大的成功。

第二个解决方法较为传统。创造一种游戏机制，即根据玩家的成绩将其进行分类，并允许他们选择与自己同级别的玩家进行游戏。这种机制常出现于多人游戏中，但它却存在着许多不足之处。所以很多玩家常常会发现，尽管自己选择的是具有相同“级别”的对手，但是最后面对的其实是非常厉害的资深玩家。实际上，在一个不熟悉的地图里玩游戏自然意味着最后的失败。创造一个能够正确评估玩家级别的分类系统其实很难。正是意识到了这个问题，微软才提出了“TrueRanking”这一创造性分类机制，其中利用了许多有效参数以便有效区分玩家等级。

第三个解决方法就是提供给玩家新手教程。在《混沌理论》的“对抗”模式中，因为我们知道游戏较为复杂，所以我们便认真思考了这一问题。因此，包含有新手教程的游戏便能够帮助玩家学习并理解如何控制角色。我们添加了一个模式让玩家只要循着一条光路以及屏幕下方的解释便能够轻松地访问游戏地图并寻找主要功能。除此之外我们也详细说明了玩家可使用的任何装备的相关元素。并且在玩家真正进入多人游戏挑战前，我们还设置了地图考核机制，玩家通过测试之后才算是真正掌握游戏设置的基本内容。

（《分裂细胞3：混沌理论》多人游戏版本中的地图新手教程。玩家可以遵循光路或者根据每隔一段时间出现的解释一步一步前进）

而大量的辅助内容会带来何种结果？新手教程虽然能够让新手玩家更轻松地开始游戏，并让他们不会轻易迷失于游戏地图中，但是却不能直接帮助他们与资深玩家进行对抗。毕竟，只是阅读一本驾车指南并不意味着你马上就能开车。《战地2》中出现了更妙的解决方法，即提供一些具有前后关系的帮助内容。当玩家从一座建筑物跳下或者从飞机上跃下时，他可以打开降落伞以避免受到重伤。但是如果玩家不能够打开降落伞而死亡后，系统就会提示他降落伞的存在及其控制方式，以便玩家重玩游戏时能够利用这一功能。如果能够考虑到这点，那么新手教程便能够发挥更大作用。

第四个解决方法便是整合一个正面或负面的“差点系统”（游戏邦注：其目的是允许程度不同的所有业余高尔夫球员能在任何球场公平竞争，从而使高尔夫运动更加富于乐趣）。根据玩家的分类，他能够受益于额外的生命值或者较少的弹药。这种机制能够让不同级别的玩家趋于部分平衡。然而，为了能够同时满足资深玩家，游戏同样也需要补偿给这些玩家新弹药或者新装备。《孤岛危机》的设计师正在利用这一方法为这款游戏的多人游戏版本创造一个智能系统。

最后一个解决方案是提供一个变量的几何控制界面。对于此类游戏的一种解决方法便是提供两种版本的用户界面，即面向于初学者的简单界面以及针对资深玩家的完整版本。虽然这种方法并不适用于所有游戏，但是却终归值得一试。

设计能够迎合所有玩家的游戏

添加一些能够帮助初学者更好地面对硬核游戏玩家的功能在某种程度上看来是有效的，但是如果我们希望多人游戏能够得到大多数玩家的认可，我们就必须在开发阶段就明确这一目标。我将列出新手玩家在多人游戏中所面临的三大问题：

用户界面

对于地图的认识

对于获取胜利策略的理解与执行

让我们看看如何才能解决这三大问题。

首先是用户界面。它的设计必须围绕一些容易理解的原则。我们都知道通过掌机上的两个模拟摇杆便能够控制游戏角色，但是对于新手来说这就不是一个简单的机制。通过实验性的游戏测试你能够了解到初学者对于游戏界面的理解与看法。一大解决方法便是创造一个自动适配的用户界面，让新手能够执行一些基本行动，并随着级别的提高而给予他们更多新功能。语音命令或者控制器，如Wii-mote的使用能够彻底改变我们与游戏间的互动。而如果你认为这些方法都过于理想化，那么你也可以选择单纯地简化用户界面。《光晕2》的界面便是一个优秀的直觉型界面，因为它并未设置过多的控制内容。

接下来是地图。我先列举出几个能够帮助玩家理解地图的方法：选择大地图而不是复杂布局，使用一些容易识别的任务目标，通过提供清晰明了的结构而维系起任务目标和地图布局间的联系，玩家能够自己定位目标，创造一个易识别的导航网络体系，提供给玩家一个地图全局布景或部分内容，或者选择非对称性地图。《战地》系列游戏中便提供给玩家一副较大的地图，但同时也提供了简单的导航体系以及清晰明了的目标。所以不要再把地图当成是什么难以解决的大问题了！

（Long Run是一张复杂但却容易通航的地图，因为它采取了不对称性设计方法）

最后便是策略问题。这是一种难以控制的游戏维度问题。在《分裂细胞》等游戏中，这一问题真的对玩家产生了巨大的影响。我认为主要有两种可能的解决方法。

第一种方法是技术条令。主要是指设立一个智能代理帮助玩家分析游戏过程并有针对性地提供建议。举个例子来说，如果第一人称射击游戏玩家长时间未有任何行动，那么智能代理便会提醒他现在很容易遭到狙击手的攻击。而如果代理发现玩家总是在使用相同的方法，它也会帮助玩家寻找新的方法。但是所有的这些都是理论上可行的内容，真正实践起来并没有那么容易。而就像我们在《战地2》中所看到的，提供给玩家一些前后关系的信息便是一种合理的方法。

第二种方法是基于概念的内容。现在已经出现了一些能够满足休闲玩家需要的多人游戏，如《反恐精英》以及《战地》系列游戏，它们主要基于一些设计选择：提供一种所有PC玩家都熟悉的游戏类型，第一人称射击游戏，容易理解的任务目标，地图布局以及清晰的导航，能够容纳更多玩家的大规模地图和游戏过程。

如果从创造易用性多人游戏的角度来看，后面两个因素便特别重要。大规模的地图能够让玩家更容易注意到并避免远处敌人的攻击。例如在《战地》中，玩家经常因为不知道敌人的所在位置而遭到攻击死亡。第二个元素是，如果游戏地图能够容纳更多玩家，那么便能够同时整合进更多休闲玩家了。实际上，当玩家是一个庞大群体的一份子时，他便能够加入团队并跟随那些了解地图以及地图策略的人而行动。

结语

我希望通过这篇文章让设计师更加清楚地了解到多人游戏地图的设计不同于单人游戏地图，必须遵循特定的架构。地图的成功依赖于合理控制每一个参数内容。设计师必须清楚，玩家可能会进入地图无数次（甚至可能同一个玩家就会这么做），所以任何一个设计漏洞都有可能被挖掘出来。

我还想补充一句，没有所谓的完美地图，但是如果遵循上述描写的这些要点，你便能够将缺陷降低至最少。

游戏邦注：原文发表于2006年11月22日，所涉事件和数据均以当时为准。（本文为游戏邦/gamerboom.com编译，拒绝任何不保留版权的转载，如需转载请联系：游戏邦）

Multiplayer Level Design In-Depth, Part 3: Technical Constraints and Accessibility

by Pascal Luban

November 22, 2006

Introduction

My first paper dedicated to multiplayer level design tackled the specific constraints imposed by the multiplayer game mode compared with that of single player. Later, my second paper detailed the level design rules that I consider to be the most important to respond to these constraints. Today, I will tackle another equally important aspect of the development, balancing.

Fine Tuning

Balancing consists of ensuring that no player or group of players can keep the advantage systematically throughout the game, by making the most of a game parameters (the power of a weapon for example) or of a weakness in the map. This problem is particularly seen in multiplayer games, because their users have plenty of time to discover the faults of the game and exploit them to their full effect. As maps are played for tens of thousands of sessions and players easily swap tricks among themselves.

A fault in a map could potentially kill the entire map by enabling a player or a group of players to reach a highly destabilizing advantage. That very problem was raised in one of the multiplayer maps we developed for Splinter Cell – Pandora Tomorrow’s Warehouse. In this map, divided into three areas, the killed defenders spawn in a small room next to the first play area. This room is obviously reserved to the defenders and the attackers are not supposed to have access to it.

After a few weeks of use, we realized that attacking players had found a technique to enter this room by taking advantage of the moment when one of the defenders walked out of it. As soon as they were inside, they could easily kill the defenders as soon as they respawned! Such a fault could have made the map unplayable. Fortunately, this was not the case, thanks to the fact that the map was divided into areas, because as soon as the mission objective of the first area was reached, the players move on to the next area.

A poorly balanced game ends up making the players lose their interest, because nobody likes fighting against an opponent who benefits from an unbalanced advantage. Note that balancing isn’t only about level design, but also the game system and the game design. Three directions must be considered to balance a multiplayer game: the level design itself the game design and the playtests.

Level Design

The first level design decision that is likely to affect the balancing of a game is the map’s size and the number of players it can support. A small map generally makes balancing more difficult, because tiny details are amplified by the density and the speed of the action. Conversely, if the map is too large, the players will get bored because encounters will be rare.

The choice of the ratio between the number of players and the size of the map is therefore very important. In most cases, opt for relatively large maps. They offer more tactical opportunities, and it will therefore are more difficult for the players to take advantage of the faults of the map.

The map layout itself can favor the balancing of the game. An open map (outdoors, for example) and the use of the third dimension (see my paper dedicated to map design) will make it difficult for bottlenecks, which could create destabilizing situations, to occur. Such maps offer more tactical opportunities than “flat” indoor maps.

Finally, the map should also offer various opportunities to use the game design features: weapons, equipment, moves, and so on. The maps of the multiplayer versions of Splinter Cell – Pandora Tomorrow and Chaos Theory include many places where an attacker can hide to prepare to ambush a defender, objects to hide behind, high footbridges to supervise a large area and accurately throw grenades, and pipes along the ceiling of rooms used by the defenders which allow the attackers to jump them.

The Game System, or The Balancing Of Opposing Forces

The idea is to provide the gamers with enough “tools” so they can find a counter-measure to a possible imbalance. The game designers who worked on the multiplayer versions of Splinter Cell – Pandora Tomorrow and Chaos Theory controlled this dimension of the game system very well. Each piece of equipment the players have at their disposal is characterized by the possibilities it offers to its user, but also by the opportunities it offers to the opponents. Here are a few examples: the defenders’ laser enables them to inevitably find the opponents by scanning the surroundings, but it also allows attackers to spot the defender from a distance and to see what he is looking at. The attackers’ camouflage clothing enables them to greatly reduce the risk of being spotted by the opponents, but it also restricts speed. The laser mine is discreet, but the attacker can easily spot its ray by activating electronic vision. This approach limits the risks of having any specific piece of equipment become too powerful.

Playtests, The Gameplay Quality Assurance

Regardless of the time you spend “planning” your game or level design in order to identify potential weaknesses, there is nothing like putting the game to the test in the hands of experienced gamers to see how badly they break it and take a malicious pleasure in exploiting its faults.

Generally, playtests are particularly useful during the development phase of a game. They have become essential for a multiplayer game. In fact, gamers – most often hardcore gamers – will spend hundreds of hours exploring every slight detail in the map, applying all the different tactics generally used in this type of game: testing all weapons and equipment, searching for any fault in the level design, and any bugs that will enable them to take advantage over their opponents. Consequently, the weaknesses in the game or level design are quickly revealed and the game soon becomes less interesting. Properly conducted playtests allow the detection of faults in the level design, or poor settings of the game parameters such as the power of weapons, health levels, and so on.

In addition to my responsibilities as the lead level designer of the multiplayer versions of Splinter Cell – Pandora Tomorrow and Chaos Theory, I also implemented and supervised the playtest structure of the Ubisoft’s D’Annecy studio where these versions were being developed. The managers of the studio were so aware of the importance of playtesting that they wanted the testing to be done in the same building, so that the development team could be directly connected to the playtest team.

How did we use the playtests?

In Splinter Cell – Pandora Tomorrow, the setting of smoke grenades gave rise to lots of playtesting.

We undertook systematic research of winning tactics – strategies that enable a player to win systematically and therefore maintain a steady interest for a game or a map. Among the most frequently encountered martingales are the “camp” points, which enable a player to cover one or more mission objectives with minimum exposure.

We put a lot of work into the game settings. Experience showed me that the intense use of certain features of a game (weapons, equipment, actions etc.) varies significantly according to a players’ profile, the time spent to get familiar with the game and, of course, the settings. Only long-term playtests that are conducted with a selected sample of gamers help ensure that the game settings remain correct after long hours of play. In Splinter Cell – Pandora Tomorrow, the setting of smoke grenades gave rise to lots of playtesting. In fact, this smoke not only blurs the view of the players, but also asphyxiates defenders if they remain inside it for too long. The size of the effect area and the duration of the asphyxiating effect are parameters which could have had an important impact if they had been set incorrectly. If the grenade had been too effective, it would have become a disproportionately powerful weapon, as it would have been enough for attackers to launch one into a passage to make it impassable for the defenders. Conversely, if the grenade had been too ineffective, it would have become tactically uninteresting and players would not have used it. Remember the point regarding the player always looking to win at any cost in my previous article. To win, players quickly stop using useless equipment, but the development resources and the memory space of the special effects associated with this equipment are lost.

Finally, we tested the accessibility of the maps and the ease of gaining control of the game.

Conducting a playtest campaign is a particularly rewarding experience for a development team. To see how real gamers use the game and how they change the use an item from its original function (as I saw in the case of proximity mines that were often used as presence detectors by the defenders) to understand why they don’t use certain equipment that seemed so cool at the design meetings. Playtests are the tool that separate what looked great on paper in a design meeting from what is more important: what the gamers will actually use.

Design Solutions to Respond to Technical Constraints

In the first part of my series, which tackled the issue of level design for multiplayer games, I introduced three technical constraints that have a particularly significant impact on the design:

The bandwidth bottleneck

The need for event synchronization

The lack of control over the players’ actions

Let’s look at a few possible solutions to these constraints.

The Bandwidth Bottleneck

Previously, we saw that developers must maintain a balance between the number of players that can be supported during a session and the complexity of actions (animations, map events, special effects etc.) that can occur. Today, the general trend is to favor the number of players rather than the wealth of interactions in the map. I am convinced that this choice will evolve, because gamers want to have the same experience in multiplayer modes that they experienced in single player, such as map animations, destructible backgrounds, and physics management. Consequently, here are a few solutions for handling the bandwidth problem.

It is possible to hide a very complex animation by masking the animation behind a flash or a cloud of smoke, therefore avoiding overloading the bandwidth. We used this technique to its extreme in the Factory map that we developed for Splinter Cell – Chaos Theory, where a whole room can be destroyed following an explosion triggered by one of the defenders. The room is full of explosive barrels, which can go off if one of the defenders hits them with a bullet or launches a grenade towards them. It is obviously not in his interest to do that, because the room’s layout would then be completely changed and the defenders’ movement would be severely limited. Such a map event would have been impossible to carry out without sacrificing bandwidth. The level designer in charge of the map succeeded in handling this event as follows: when the room blows up, all those inside it are instantly killed. Consequently, they cannot see the explosion and if some sly gamer has the idea to fire from outside the room, the smoke prevents him from seeing the result of his action (see the screenshots below).

In this room of the Factory map (Splinter Cell – Chaos Theory), the defenders’ movement is easy: there are few ground obstacles and the footbridge goes around the room on a higher level…

…but if one of the defenders triggers the explosion of the explosive barrels, the room changes completely. Movement on the ground is slowed down because of collapsed wall sections and the footbridge is a pile of scrap metal. Defending the room then becomes much more complicated.

A second solution consists in scattering bandwidth consuming elements around the map. In this way, no two complex elements will ever occur simultaneously. It is essential to ensure that they will never interact with each other.

Another option is to try to mask the movement of certain mobile objects such as elevators, whose movement may be obscured by opaque walls. Finally, remember to include the possibility for a player to throw a grenade in an elevator box while the latter gets ready for movement. The explosion should not interfere with the movement.

Finally, one last solution is to work on compressing the data exchanged between the game machines.

The Need for Event Synchronization

Synchronization problems account for most of the dissatisfaction among gamers. When a good player places the cursor on a moving target and pushes the trigger, he expects the bullet to reach the target immediately and exactly where he aimed at. If you are working on an FPS, this problem should be at the core of the development process. I see two possible solutions to this problem:

To develop a multiple server architecture. Traditionally, in a multiplayer session, one of the game machines acts as a server and synchronizes all the interactions resulting from the actions of the client machines. This architecture guarantees the synchronization among all machines, but slows down the data transfer, because the information related to an interaction between clients A and B must pass through the server first. With multiple server architecture, each machine acts as a server and a client at once. In this way if player A interacts with player B and the other players are not involved, data is exchanged directly between A and B. This solution was probably used in the Xbox version of Soldier of Fortune, a game appreciated by FPS “pros” for its precision. The multiple server architecture also offers another advantage compared with classical architecture, where a loss of connection with the server puts an end to the entire session. In case of multiple server architecture, players may start and end a session as desired.

A less elegant solution from a technical standpoint consists in using only weapons with an area effect, such as a shotgun, a rocket-launcher, or a grenade-launcher.

The Lack of Control over Players’ Actions

The objective is to avoid that too many players find themselves in the same spot, so as to limit the number of interactions among them. Once again, the solutions are related both to the game and to the level design.

Increase the number of mission objectives and scatter them throughout the map. These two mechanisms were successfully implemented in Splinter Cell and Battlefield series of games. In the latter, players who select an engineer profile have access to many secondary objectives, such as the destruction of radar stations.

Another method to encourage the players to spread apart is to give them access to weapons that require them to preserve a certain distance from their foes. Battlefield also uses this mechanism by allowing the players to pilot a plane or control a turret.

Finally, my last recommendation is to avoid using small maps. However, the balancing between the size of the map and the number of players it can support is a delicate decision to make, because if the map is too large compared with the number of players, the player will soon get bored.

These “second best” solutions are far from being able to provide a long-lasting response to the multiplayer-specific technical problems. Other solutions exist. Essentially, my objective is to draw the attention to these problems so that they be taken into account very early in the development cycle of a game. I encourage my readers who have a solid technical experience to open a discussion thread and come up with additional solutions in the forum.

Getting Casual Gamers to Play

In my previous papers, I presented my suggestions to very specific challenges of multiplayer level design. I will end this series with what probably represents the main challenge: to make multiplayer games more accessible.

The very essence of a multiplayer game is to enable players of all levels to gather and play against each other. This is where the interest for this type of game lies, but this is also what makes it so difficult for the beginners. Playing against real human beings is intimidating, even if you are hiding behind a GamerTag. Yet, what happens when a casual gamer ventures into a multiplayer session is quite typical. Confronted with gamers who have mastered the game more than him, he repeatedly suffers humiliating defeat. It’s therefore not surprising that multiplayer games are reserved for hardcore gamers. Nobody likes suffering defeat after defeat. If we want to make the multiplayer games accessible to the mass market, we have to handle this problem. The solutions lie both in the game and in the level design.

In my opinion, there are two solutions to this problem:

Add beginner-friendly features

Develop a game designed for casual gamers, while bringing enough depth to the game to satisfy experienced gamers as well

Features for Beginners

Let’s begin by reviewing features that may be added to a traditional multiplayer game to make it more accessible. This is something that we tried to do with the multiplayer mode of Splinter Cell – Chaos Theory.

The first solution is simple and particularly effective. It simply consists in adding cooperative modes. Gamers will not play against other gamers in flesh and bones, but against opponents, bots controlled by the game AI. This solution allows gamers of all levels to play together without being humiliated by other gamers, as bots are rarely as unpredictable and dangerous as their human counterparts. It allows experienced gamers to show themselves to best advantage by sharing their experience with the beginners. Finally, the cooperative game may be an extraordinary source of joy, since working together to reach a common goal is one of the driving forces of the human adventure. A “coop” multiplayer mode was developed for Splinter Cell – Chaos Theory by the Canadian studio Ubisoft. This mode was a huge success.

The second solution is just as traditional. It consists in developing a mechanism for classifying the players according to their victories and giving them the freedom to choose to play only with other players of the same level. This mechanism is present in many multiplayer games, but its efficiency often leaves much to be desired. It is therefore not unusual to find yourself playing against much more experienced players, even of the same “level”. In fact, playing on an unknown map is all it takes to ensure your defeat. To develop a classification system that is accurate enough to correctly evaluate a player’s level is much more difficult than it seems. Aware of the problem, Microsoft has propose ‘TrueRanking,’ an innovative classification mechanism that takes into account a very large number of parameters to make a player’s rank.

The third solution is to make the gamer learn the game by means of tutorials. Various types of tutorials may be created, outside the game and integrated in it. In the “versus” mode of Chaos Theory, we went deep into this matter, as we knew the game was hard to learn. Thus, the game includes a classic tutorial, made up of mini-sessions where the gamer learns how to handle his character. We added a mode that enabled the gamer to visit the game maps and discover the main features, in which all he had to do was follow a path marked by a light path and explanations (see the screenshot below). We added explanations to each element of equipment the gamers had at their disposal. We even made the player pass an examination map to make sure he understood the basics of the gameplay before giving him access to the multiplayer sessions.

The tutorial for map exploration in the multiplayer version of Splinter Cell – Chaos Theory. The path to follow is indicated by a light path and explanations are displayed at regular intervals.

What were the results of this abundance of help topics? The tutorials proved beneficial to get the new gamers started and prevent them from feeling completely lost in the map and in the game in general, but they were inadequate to give them a chance against the experienced gamers. After all, you cannot learn to drive just by reading a car’s manual. A better solution can be seen in Battlefield 2, where certain help topics are contextual. Thus, when the player jumps off (or falls off?) a building or ejects himself from a plane, he can avoid a fatal fall by opening his parachute. But if the player fails to open it and dies, a message reminds him of the existence of the parachute and how to control it when the player resumes the game. This approach offers significant potential as far as tutorials are concerned.

A fourth solution may be to integrate a positive or negative handicap system. Thus, according to the gamer’s classification, he can benefit from additional health points or from less ammunition. A mechanism such as this would allow a partial balance of the game among players of different levels. However, in order to be accepted by experienced gamers, the game would have to compensate them with new animations or new equipments. An intelligent system using this method is currently being designed for the multiplayer version of Crysis.

Finally, the last solution I propose is to provide a variable geometry controlled interface. Certain games, such as those of the Splinter Cell series, require the player to master a particularly complex interface. For such games one solution would be to offer two versions of the interface, a simple one for beginners and a full version for more experienced players.

This idea cannot be applied to all games, but it may be worth trying.

Games Designed to Be Accessible to All

Adding features that are meant to help the beginner face hardcore gamers may be useful to a certain extent, but I think that if we want to make the multiplayer game accessible for the majority of gamers, we must develop it in this direction from the design stage. Here are the three issues the new gamer is confronted with when he enters a multiplayer game:

The interface

The knowledge of the maps

The understanding and implementation of winning tactics

Let’s see how we can address these three problems.

Let’s begin with the interface. It should be designed around easy to access principles. We are all acquainted to controlling a character by means of the two analogue sticks on a pad, but is this mechanism easy to control by a beginner? Experimental playtests would probably provide a lot information on how the beginners comprehend and learn to use a game interface. One solution that should be tested is to develop an adaptive interface that would enable the beginners to carry out basic actions and which would provide them with new features as their level improves. The use of voice commands or of a controller such as the Wii-mote could revolutionize the way we interact with our games. And if these solutions seem too utopian, it is always possible to simplify the interface. The interface of Halo 2 is a great example of an intuitive one, because it is not overburdened with controls.

Let’s go on to the maps. In a previous paper dedicated to level design, I described various solutions to facilitate the understanding of a map. let me repeat some of them: favor the large maps rather than the complex layouts, use easy to identify mission objectives, create a strong link between the mission objectives and the layout in such a way that by simply understanding the structure, players can locate their objectives, develop an easy to identify navigation network, enable the players to have a global view of the map or a part of it, or favor asymmetrical maps. Note that the games of the Battlefield series offer very large maps, but simple navigation and understanding of the objectives. The map size is not the enemy!

Long Run, a complex yet easily navigable map thanks to its asymmetrical design.

Finally, there are the tactics. It’s the game dimension that is the most difficult to control. In a game such as Splinter Cell, it really is the one that makes the difference among gamers.

In my view, there are two possible ways to approach this problem.

The first is of technical order. It lies in developing an intelligent agent who analyzes the player’s game and makes recommendations accordingly. For instance, if a FPS gamer remains static for too long, the intelligent agent would remind him that he is too vulnerable to a sniper attack. The agent could also help the player discover new paths if it realizes that the player keeps using the same ones. Attractive as it may seem on paper, this approach would probably be complex to develop. However, the idea to provide the gamer with contextual information works, as we could see in Battlefield 2.

The second approach is conceptual. There are already multiplayer games that are relatively easy to pick up for casual gamers, such as Counter Strike and the games of the Battlefield series. This simplicity lies in several design choices: a game style that is known to almost all PC gamers, the FPS, easy to understand mission objectives, a layout that makes the map navigation easy (at least for Battlefield), large maps and sessions that are able to support many players.

I find the latter two factors particularly interesting from the perspective of making a multiplayer game accessible to everybody. The large map size provides the gamers with more opportunities to easily notice and avoid the remote attacks of the opponents. This can be seen in Battlefield, where gamers often lose their lives progressively, due to the lack of precision of the enemy fire. The second factor, the large number of players in a session, also seems favorable to integrate the casual gamers. Actually, when a gamer is part of a large group, he can join the team and just follow a team member who knows the map and the map’s tactics.

Conclusion

I wanted this series of articles to be practical in showing that the design of multiplayer maps must follow its own specific structure, different to that of single player maps. The success of a map lies in the successful control of many parameters each equally important. Designers must be aware that their maps will be played hundreds of thousands of times (possibly by the same player), so the faults present will come out.

In closing I would like to remind you that there is no such thing as a perfect map, only those which follow certain points described here to their limits. （source:gamasutra)